The invention relates generally to polymeric sprocket wheels which include sleeve bearings. More particularly, the invention relates to improvements in sprocket wheels which are intended for use in submerged, corrosive environments, such as in wastewater settling tanks.
It has been heretofore proposed to provide sprocket wheels fabricated from polymeric materials. It is also been heretofore proposed to provide polymeric sprocket wheels of split design, which can easily be installed without removal of a shaft on which the sprocket wheel is designed to be mounted. U.S. Pat. No. 4,631,974 discloses a sprocket wheel having these features.
It has also been previously proposed to provide sprocket wheels including a split sprocket sleeve adapted to be clamped to a static shaft, and also including a split sprocket portion adapted to be mounted on the sprocket sleeve for rotation relative to the sprocket sleeve about the shaft. Attention is directed to Envirex Inc. Bulletin 315-94, which discloses a sprocket wheel including a sprocket sleeve. Other references relating to bearings and surfaces adapted to slidingly contact other surfaces include the Reuter et al. U.S. Pat. No. 2,951,053; the Melton et al. U.S. Pat. No. 3,010,733; the Thomas U.S. Pat. No. 3,094,376; the McCutchen U.S. Pat. No. 3,220,786; the Voaden U.S. Pat. No. 3,957,939; and Cooper et al. U.S. Pat. No. 4,238,039. Attention is also directed to German Patent 1,575,362; German Patent 1,961,946; Great Britain Patent 1,359,215; and Netherlands Patent 7412640.